Currently, demands on various display devices increases along with the development of the global information society, so great efforts have been made for the researches and development on various flat-panel display devices, e.g., liquid crystal display (LCD), plasma display panel (PDP), electroluminescent display (LED) and vacuum fluorescent display (VFD). Various flat-panel display devices have been developed as displays for various devices.
Along with the development of the technology, a touch display device having both a touch function and a display function has attracted more and more attention due to its operability. Along with the development of the touch technology, a capacitive touch technology has been widely used due to its advantages such as touch sensitivity and a capability of supporting a multi-point touch operation.
For a conventional single-layer touch panel structure (e.g., On-Cell or One Glass Solution (OGS)), a transparent conductive layer is formed at a surface of a glass substrate, so as to form a touch electrode and an electrode lead through exposing, developing and etching. However, coverage ratios of a touch layer at different portions of the touch panel are different from each other, so light transmittances of the touch layer at different regions of the touch panel are different from each other. As a result, the entire touch panel may have an uneven light transmittance, and bright and dark stripes may occur alternately during the touch and display procedures.